1. Field of the Invention
The present invention relates to a laser processing method.
2. Related Background Art
A pulsed laser beam is radiated onto a work piece to process the work piece. A laser processing technique described in Heinz P. Huber, et al., “High speed structuring of CIS thin-film solar cells with picosecond laser ablation,” Proc. of SPIE, Vol. 7203, (2009) (Non-Patent Document 1) radiates pulsed light with pulse width of approximately picoseconds onto a CIS (Copper-Indium-Diselenide, CuInSe2) thin film, which is formed on a transparent glass plate, to process the thin film (ablation). In the laser processing technique described in Non-Patent Document 1, a model “picoREGEN IC-1064-1500” manufactured by High Q Laser Inc. is used as a pulsed laser light source. This pulsed laser light source employs a mode lock structure, has a regenerative amplifier, and outputs pulsed light with pulse width of approximately picoseconds.